1. Field of the Invention
The present invention relates to a television receiver and, more particularly, to a muting apparatus for a television receiver that suppresses the sound generated from a first video signal while the receiver is showing a picture generated from a second video signal.
2. Description of the Prior Art
The picture being recorded by a video camera cannot be seen directly, so the video signal generated by the camera is typically fed to a television picture tube to be monitored. The picture tube in a conventional television receiver can be conveniently used for that purpose.
Conventional television receivers include both a video system and a sound system. The receiver picks up broadcast video signals, which include a video component and an audio component, and the video and sound systems of the receiver generate a television picture and its accompanying sound from the respective components of the broadcast signal.
When the television receiver is used as a video camera monitor, the locally produced video signal from the camera is supplied to the receiver's video system rather than the broadcast video signal. The audio component of the received video signal continues to generate sound, but of course that sound does not correspond to the television picture being generated from the camera-supplied video signal. The only known solution to this picture-sound mismatch is to turn down the volume of the sound whenever the receiver is used as a monitor for the video camera.